The liquid crystal display (LCD) is one of the most widely used flat panel displays. According to light sources used in the LCD, the LCDs are divided into a transmissive LCD and a reflective LCD. The transmissive LCD uses a backlight as the light source, and after transmitted through a polarizer and a liquid crystal panel, only about 10% of light from the backlight is obtained, and therefore, in order to improve a brightness of the transmissive LCD, a power consumption of the backlight needs to be increased. The reflective LCD can only be used during daytime or in the presence of an external light, and cannot be used at night or in the situation of a weak light. Therefore, a transflective LCD is developed correspondingly, which uses the backlight or the external light as the light source according to the environment.
FIG. 1 illustrates a cross-sectional view of a current transflective LCD, and the current transflective LCD comprises: an upper substrate 160; a lower substrate 150; a liquid crystal layer 180, interposed between the upper substrate 160 and the lower substrate 150; and a backlight 170, located at a side opposite to the upper substrate 160 of the lower substrate 150. A common electrode 162 is interposed between the upper substrate 160 and the liquid crystal layer 180, and a pixel electrode is divided into a transmissive region electrode 164 and a reflective region electrode 152, wherein the transmissive region electrode 164 is located in a transmissive region t of the lower substrate 150, and the reflective region electrode 152 is located in a reflective region r of the lower substrate 150. The color filter 168 is located between the upper substrate 160 and the common electrode 162. In a transmissive mode, the light 174 emitted from the backlight 170 passes through the lower substrate 150, the transmissive region electrode 164, the color filter 168 and the upper substrate 160. In a reflective mode, an environment light 172 is incident on the reflective region electrode 152 through the upper substrate 160, the color filter 168 and the common electrode 162, and then is reflected by the reflective region electrode 152 and passes through the color filter 168 and the upper substrate 160 again.
In the transmissive region t, the light 174 emitted from the backlight 170 only passes through the color filter 168 once, while, in the reflective region r, the environment light 172 passes through the color filter 168 twice, and thus, a color saturation of the reflective region may be larger than that of the transmissive region. Therefore, a method of forming a hole or a slit in the color filter 168 is used, so that the color saturation of the reflective region tends to be consistent with that of the transmissive region.
FIG. 2 illustrates a plan schematic view of a current color filter substrate. As shown in FIG. 2, the color filter substrate comprises three kind of pixel region of R (red), G (green) and B (blue), and a boundary region between adjacent two pixel regions is arranged with a black matrix, each pixel region is divided into a reflective region and a transmissive region, and the black matrix is located between two adjacent color filters. The reflective regions are respectively denoted as R(r), G(r) and B(r), the transmissive regions are respectively denoted as R(t), G(t) and B(t), the color filters are respectively denoted as 210R, 220G and 230B, corresponding light holes in the pixel regions are respectively denoted as 210W, 220W and 230W, and the black matrix is denoted as 240. The color filter substrate with the black matrix and the light holes can lower the color saturation of the reflective region by adjusting a size of the light hole, however, as the black matrix is used to prevent the light leakage, the color filter substrate has a relatively low aperture ratio and a display screen having the color filter substrate has a relatively low brightness.
FIG. 3 illustrates a plan schematic view of another current color filter substrate. Such color filter substrate comprises three kinds of pixel region of R (red), G (green) and B (blue), and each pixel region is divided into a reflective region and a transmissive region. The reflective regions are respectively denoted as R(r), G(r) and B(r), the transmissive regions are respectively denoted as R(t), G(t) and B(t), the color filters are respectively denoted as 310R, 320G and 330B, and corresponding light holes in the three pixel regions are respectively denoted as 310W, 320W and 330W. For such color filter substrate, the color filters in different pixel regions are directly adjacent to each other and there is not provided black matrix between two adjacent pixel regions, thus, an aperture ratio and a screen brightness are relatively high, however, each two adjacent pixel regions are directly adjacent to each other, and thus, a relatively high alignment precise between the upper substrate and the lower substrate is required, and when the alignment precise is slightly low, the poor display may be caused and the color mixture may occurs between two adjacent pixel regions with different colors.
Therefore, as for the current color filter substrate used in a transflective liquid crystal display device, when an black matrix is provided, a lower aperture ratio and a lower screen brightness may be caused; in a case that the black matrix is not provided between adjacent color filter with different colors so as to increase the aperture ratio, when the alignment precise between two substrates is slightly low, the poor display may be caused and the color mixture may occurs between two adjacent pixel regions with different colors.